Sheet metal punch machine



y 7, 1935. s. T. BALFE SHEET METAL PUNCH MACHINE Original Filed Dec. 11,1931 5 Sheets-Sheet l I N V EN TOR.

flea/9e 7." Ba/f'z Q A TTORNEYJ May 7, 1935. G. T. BALFE SHEET METALPUNCH MACHINE Original Filed Dec. 11, 1931 3 Sheets-Sheet 2 INVENTOR.G'earye 7 50/7 52,

ATTORNEY) y 1935- cs. T, BALFE 2,000,208

SHEET METAL PUNCH MACHINE Original Filed Dec. 11, 1951 I5 Sheets-Sheet 34 I N V EN TOR.

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gArrokNEx f Patented May 7,1935

PATENT OFFICE SHEET METAL PUNCH MACHINE Geom 'r. Balfe, mam, "16L, ma

Detroit Gasket 4; Manufacturing Company, Detroit, Mich, a corporation ofMichigan right! application December 11, 1931, Serial No. 580,415, whichintllnl is a division of Serial No.

479,734, September 4, 1930, now Patent No. 1,843,438. Divided and thisapplication June 3, 1932, Serial-N0. 615,233

5 of, perforating sheet'material such as metal,

and more particularly to the forming of a large number of closelyadjacent apertures in such a sheet, and in such a manner as not toremove any of the metal from the sheet and to give form and shape to themetal about the perforation.

An object of my invention is the manufacture of closely. perforatedsheet metal plates rapidly and economically. The invention comprises anew type of machine for producing metal sheetsthus characterized and anew process of their manufacture.

It is shown as embodied in mechanism for producing a reticulated metalsheet having a particular type of perforation and wherein the sheet ispunched from opposite sides to produce apertures including oppositelydirected minute tangs closely spaced from one another throughout theentire surface area of the sheet on both sides thereof and arrangedafter a specific fashion.

There are numerous uses to which sheet metal so perforated may beplaced. One use is as a base for a gasket structure such as. I havedescribed and claimed in my copending application Serial No. 420,331,filed January 13, 1930, No. 1,776,140, issued September 16, 1930, whichshows open ended protuberances having tangs projecting from the bottomthereof. Great difilculty has been experienced in perforating sheetmetal as above described wherein tangs extend in opposite directionsalternately throughout the width and length of the sheet.-

It is desirable that the tangs project from opposite faces in a uniformstyle and arrangement and that they be formed without otherwisefracturing the metal and that the sheet so perforated retain suflicientstrength for the purpose for which it is to be employed.

Consequently I have provided a method of producing such sheets by whichthe perforations may be formed in succeeding rows, all perforations in arow being simultaneously formed, and the adjacent perforations of eachrow being formed from opposite sides of the sheet so as to producespaced tangs along each row which alternately project from oppositesides to produce the aforenamed results.

My improved machine includes a plurality of individual punch unitmembers provided with male punches so disposed in the relativearrangement of the several units as to carry out the desired process.The several punch unit members are arranged to act upon a sheet of metalto form successive rows of perforations therein. 5

Preferably the pimch unit members are in the form of individual sheetsteel discs having peripheral punch teeth and secured in a row inclosely spaced arrangement upon a rotatable arbor. A similancooperatingopposed arbor carrying similarly arranged discs is here illustrated withthe discs of the two arbors enmeshed. Each disc, in its punch teeth,embodies a male die and a portion of a female die.

Arranged between each adjacent pair of discs is an individual sheetmetal stationary stripper plate which serves to strip the metal sheetfrom the male dies of the rotating disc. These stripper plates areindividually removable as are the discs and they are also arranged inpairs, spaced apart in the same plane, a pair between each pair ofspaced discs on an arbor. Due to the enmeshed cooperation of the discseach pair of stripper plates is disposed between a pair of spaced discson each arbor.

The stripper plates establish a planar guide for the metal sheet beingacted upon by the discs. They also strip the plate after perforationfrom the discs. Each line or row of stripper plates, the edges of whichform a. planar guide, act as an anvil for the opposed discs andcooperate with the female die portions 'of the adjacent rotatable discsto form the female dies.

A further object of the invention is to so pre sent the respective maleand female dies of the discs to each other that a clearance between eachmale and female die is provided during their interengagement whereby themetal is tiepressed and perforated to produce tangs and the tangs givena form as the process continues.

An additional feature of the invention resides in the means employed fordistributing a cooling agent, usually a lubricant such as oil, upon thedie members, and the provision of means for wiping or cleaning the sheetmetal after it has been acted upon by the die members, to remove anyfilm of cooling material which may be coated or have collected thereonand thus present the finished material in condition for subsequentoperations without further treatment.

Other meritorious features of my improved method and machine will beobvious from the following description taken in conjunction with thedrawings wherein:

Figure l is a cross section on the line I-l of Figure 2.

Figure 2 is a vertical section along the line 2-2 of Figure 1.

Figure 3 is a section along the line 3-3 of Figure 2.

Figure 4 is an enlarged section along the line 4-4 of Figure 2.

Figure 5 is a detail view in section showing the engagement of the diemembers. I

Figure 6 is a detail view showing the action of the die members upon thesheet of material being treated.

Figures 7, 8, 9 and 10 are detail views of the die member and associatedparts.

My punch machine comprises a base or frame l0 having upright standardsl2 and I4. These standards provide bearings for two opposed rotatablearbors 6 and I8. Each of these arbors is provided with gear wheels 28and 22 which are of identical diameter and possess the same number ofteeth. Arbor I8 is driven through gear 22 from a suitable power sourceas by means of a chain, and the two arbors l6 and I8, therefore, rotateat the same rate of speed.

Secured transversely across the front and rear of the uprights l2 andI4, as by means of screws 26, are spaced keyway members 28 and 88.Similarly disposed keyway members 32 and 34 are secured to the oppositesides of the upright standards in a like manner. A guide and feed plate36 is secured by means of the bracket 38 to the keyway 28 and assists infeeding the metal strips between the shafts l6 and I8.

Keyed to the keyways 28, 30, 32 and 34 and freely surrounding orpartially embracing each of the shafts I6 and I 8 to permit freerotation of the shafts with respect thereto, at closely spaced apartintervals along each of the said shafts, are my stripping discs 40having keyways 40', as shown in Figures 7 and 10. The apertures 42,where a disc, as shown in Figure 7, is employed, are somewhat elongatedfor purposes to be hereafter brought out. Spacing discs or bearingwashers 44 are keyed to the shafts l6 and I8 by means of keys 24 fixedto the arbors within the apertures 42 of stripping discs 40. These twodiscs occupy the same plane, but the spacing disc 44 is ofinfinitesimally greater thickness than the stripping disc 48. It may,however, assume various thicknesses as occasion may require.

The punching discs 46, about the circumference of which the punch teeth48 are arranged are keyed to the shafts l6 and I8 and held in spacedrelationship thereon by the spacing discs 44. As illustrated in Figures3, 4 and 5, the teeth 48 of the two discs 46 on each side of eachspacing disc 44 are disposed in staggered relationship to each other.The punch discs, of course, revolve as a unit with the arbor upon whichthey are mounted.

As already stated, the apertures 42 in the stripping discs 40 areslightly elongated as shown at 4| in order that their peripheral edgewill be subjected to minimum pressure and frictional wear from therotating spacing disc or bearing washers 44 which rode therein. This isshown best in Figure 5.

It will be seen from Figures 2 and 3 that the cooperating punch discs 46keyed to the two shafts l 6 and l 8 occupy the same plane and mesh withone another. The male dies of one disc cooperate with the adjacentstripper discs to perforate the metal sheet. In the operation of themachine as the metal sheet is fed along the guide plate 36, it is caughtby the teeth of the rotating punch discs. A bevel 58 is provided at thefront of the straight edge portion of each of the stripping discs 40 tofacilitate the ingress of the metal sheet. Inasmuch as the teeth 49 meshand are being rotated in opposite directions, it will be seen that thesheet of metal will be punched alternately in opposite directions byeach upper and lower pair of punch discs 46 as it progresses. It willalso be seen that, inasmuch as the teeth 48 of the punch discs 46 whichare located on opposite sides of the stripping discs 49 are staggered,the apertures punched in the sheet of metal and extending in a row willbe staggered transversely across its width. The rows are punched andformed in succession.

The metal which is displaced to form the aperture is not removed fromthe sheet and since the punch teeth 48 are rotating at the moment theycommence their punching operation on the sheet of metal, the punchproduces a small tang in the metal on the side opposite that from whichit is punched. It is this tang, in contradistinction to a clean cutaperture, which renders the resultant sheet of metal particularlyadaptable as a base unit for the gasket described in my aforesaidapplication. The projecting tangs and the sides of the apertures aregiven a curved shape as shown in the copending application hereinreferred to and it is believed that this results from the rolling actionof the teeth over the sheet, and that the sheet is first deformed andthe metal partially shaped for the resulting aperture and tang beforethe metal is actually pierced and that following the piercing the tangis further bent and shaped.

Each row of stripping discs not only functions to strip the metal sheetfrom the rotatable discs but it also functions as an anvil to receivethe thrust of the opposed row of rotating punch discs. In addition italso serves to cooperate with the female die portions of the adjacentrow of rotating punch discs to form the complete female dies for themale dies of the opposed row of rotating punch discs.

A receiving plate 52 is mounted upon a second bracket 54 which issecured to the keyway 34 on the egress side of the punch machine, andthe end of the straight edge portion of each of the stripping discs 40is cut away as at 56 for the purpose of freeing up the sheet of metal asit issues from the rotating punch discs.

In the drawings, particularly in Figure 7, I have illustrated the slightelongation of the apertures 42 in the stripping discs 40, and haveindicated this at 4|. The arbors are adjustable toward or from eachother to provide for movement of one or both arbors. Preferably theupper arbor is made adjustable by means of spacer blocks mounted in theframe and supporting the bearing blocks. Suitable means are provided forfirmly securing the arbor in any one of its adjusted positions, as forexample, spacer blocks may be disposed in the frame above the bearingblocks, and by means of adjustable screws or bolts suitably tightened tohold the bearing blocks between the spacer blocks.

Any suitable adjusting means for the upper spacer blocks may beemployed, and the spacer blocks will preferably be slidable in guidesarranged on the frame.

Instead of employing stripper plates of the form shown in Figure 7,these may be made arouate or semi-circular, as shown in the drawings,and in detail in Figure 10. With such a construction, the upper andlower key ways will be made vertically adjustable on the frame so as todispose the opposed meeting edges of the stripper plates in the propervertical spaced apart relation. By using arcuate or semi-circularplates, any possibility of wear, due to friction between the plate andthe piercing disc, is eliminated.

It will thus be seen that the arbors and stripper plates may be adjustedto vary the depth of the depression and the length of the tang asrequired.

It will be understood that, while the machine is operated at relativelyhigh speeds, the treatment of the metal is gradual so far as thebending, piercing and forming operations are concerned. This will bereadily understood from Figure 5, where there is a gradual bending tothecenter, piercing and a gradual forming at the center to bend the tangand form it.

It will be observed that the stripper plates 40 illustrated in detail inFigure 10 are provided with recesses 60 in the side edges thereofadjacent the lower edge. The recesses 60 receive the respective keyways28, 30, 32 and 34 and are vertically adjustable towards or away fromeach other, by

reason of the said keyways being slidably mounted in a verticaldirection on the frame of the machine.

I may use either a stripper member of the form illustrated in Figure 7,but prefer to use a stripper member 40 of the type illustrated in thedrawings and in detail in'Figure 10. By employing a stripper member asshown in Figure 10 of this application, the respective stripper membersare adjustable with respect to the arbors within very delicate limitswithout moving the arbors and it is only where spacing of the strippermembers is extended that the arbors need be moved; at the same time agreat saving in metal is obtained.

Referring to Figure 2, I disclose nozzles 63 and 64 at the feed in sideof the machine adapted to throw a spray of lubricant and cooling mediumupon the die members and associated parts. On the other side of themachine, I disclose a blast apparatus which acts to remove any coolingmedium or lubricant which has formed as a film upon the perforatedsheet. Thus the sheet is caused to pass beneath a blast hood 64' havingan enlarged outlet and over a transversely disposed perforate grid 66having a dimension substantially that of the blower outlet 65. The .grid66 will support the perforated material and the action of the blast 64'is to force any lubricant upon the perforated plate or within theopenings and projections downwardly into the outlet 67 communicatingwith the openings of the grid 66. A suitable suction fan is sometimesconnected to the outlet 61 and, therefore, the sheet is not only actedupon on its upper surface by the blower, but is subjected to a suctionon its undersurface so that a thorough cleaning is obtained. Thissuction apparatus is not essential, the blast delivered to the uppersurface of the sheet being usually suflicient. The lubricant isdelivered from the outlet 61 to a suitable collector, not

shown, whence it may be pumped back and reused. The blower and gridsubstantially enclose a. sheet of formed material delivered from themachine, being of sufficient transverse dimension for this purpose. Thesurface of grid 66 is flush with receiving plate 52 as shown in Figure2.

It will be observed that the grid which preferably consists of aplurality of transversely or longitudinally spaced bars is substantiallyflush with the stripper plates forming therewith a continuous path,whereby the sheet is not subjected to any bending or otherwisedistorted. Furthermore, the cleaning action takes place at once as apart of the continuous operation of forming the sheet being immediatelysubsequent to the delivery of the sheet from the die members.

A pan G8 is disposed at the base of the machine to collect any of thecooling medium which drips therefrom.

It is to be observed that by reason of the construction employed thatthe punching operation is a continuous process involving the steps offorming the depressions, piercing a portion of the bottom of eachdepression to produce thereby a tank and then simultaneously giving formand shape to the uncut wall of the depression and to the tang, whereby aprotuberance having a tang extending beyond the plane of the sheet isformed.

In this connection, it is to be observed-that the stripper plates whichform a part of the female die members effectively aid not only in theshaping and forming operation, but also to maintain undistorted thespace between the respective projections, so that the plane of the sheetis not changed. I

I desire to refer particularly to Figure 2 and Figures 5 and 6. It is tobe observed upon reference to Figure 5 that the intermeshing teeth 48engage each other, whereby a clearance is provided. Thus, in Figure 5,it will be noted that initially the point of the male die bears againstthe right side of the female die, leaving a space between the left sidesof the respective die members. As the rotary motion of the die membersprogresses, the space between each side of the male die and each side ofthe female die becomes equal and then the tooth point moves toward theleft side of the female die, whereby a space is created between theright side of each die. In this manner, the metal is first deformed ordepressed and thereafter perforated and the metal at the bottom of saiddepressed portion is formed into a tang extending beyond the plane ofthe sheet. In other words, the initial action of the die members is todepress the metal forming closed protuberances and thereafter the bottomof such protuberances is pierced and perforated by the teeth of the diesand the metal of such bottom is not removed, but instead formed into atang which, as stated, is beyond the plane of the material and theprotuberance. This rolling motion after the piercing of the sheet notonly gives form to the tang, but to the depressed portion orprotuberance as well.

The metal or other strip material may be fed in lengths or continuouslyfrom a roll and it will be seen that all of the operations areconsecutive to produce the finished product, and that any creases orbends in the sheet are ironed out in its passage throughthe machine byreason of the stripper plates.

In some cases I may dispense with the suction fan belowthe grid.

In addition to cleaning the sheet of films of the cooling medium whichmay collect thereon, the cleaning apparatus acts to remove any metalparticles and other undesirable matter on the sheet. Thus the hood andgrid presenting opposed enlarged openings effectively enclose the sheetwhile traveling therethrough and prevent any particles from escaping andinjuring workmen.

While the above generally described method of punching sheet metal inthis particular way and the mechanical elements utilized for thatpurposeare both novel, various other means for carrying out my method, as wellas various modifications of the assembled structural units will beapparent to those skilled in the art and for that reason I intend tolimit myself only within the scope of the appended claims.

This is a division of my copending application Serial No. 580,415, filedDecember 11, 1931, which,

in turn, is a division of application Serial No.

479,734, filed Sept. 4, 1930, Patent No. 1,843,438, Feb. 2, 1932.

To reiterate the process of this invention, it comprises making thegasket reinforcing material by presenting the sheet metal to engagementwith a rotating tooth member, piercing the metal at each point ofengagement of the tooth with the sheet and forming openings and wallsextending laterally from the sheet about the openings and continuing thepiercing operation and cutting a narrow portion of the metal in advanceof each tooth at one side of each opening substantially in the plane ofrotation of the teeth and pressing the severed metal laterally of thesheet and forming an elongated wall at said side of the opening whichconsistutes a. deformable tang for engaging the gasket material.

The gasket will be made by applying layers of the gasket material upon asubstantially coextensive sheet of the sheet metal prepared inaccordance with this invention and compressing the same together,whereby the tangs will penetrate the gasket material layers and bedeformed either below the plane of the outer surface of the gasketlayers, or forced entirely through the gasket layers and bent over atsubstantially right angles to lie in the plane of the outer surfaces ofthe gasket layers or the top edges of the deformed tangs will liesubstantially in the plane of the outer surface of each gasket layer.

I claim:

1. A machine of the class described comprising opposed die members, anda cleaning instrumentality comprising a blower and a grid disposedadjacent the die members for cleaning a sheet of material immediately itpasses from the die members, said grid being substantially flush withthe path of travel of the sheet from said die members.

2. A machine of the class described comprising opposed die members, anda cleaning instrumentality comprising a perforate grid with a blower anda suction means on opposite sides thereof and disposed adjacent the diemembers,

said cleaning instrumentality acting on opposite sides of a sheet forcleaning the sheet of material immediately it passes from the diemembers, said grid being substantially flush with the path of travel ofthe sheet from said die members.

3. A machine of the class described comprising opposed die members, anda pneumatic cleaning instrumentality disposed adjacent thereto forcleaning a sheet of material immediately it passes from the die members,said instrumentality comprising a grid disposed flush with the path oftravel of the sheet from the die member 4. A machine of the classdescribed comprising opposed die members, a pneumatic cleaninginstrumentality disposed adjacent thereto for cleaning a sheet ofmaterial immediately it passes from the die members, saidinstrumentality comprising a blower acting on the upper surface of thesheet, and a grid over which the sheet passes and forming a continuationof the path of travel of the sheet, means for supporting a sheet in itstravel past the die members, said grid being substantialy flushtherewith.

5. A machine of the class described comprising die members, a cleaninginstrumentality comprising a blower arranged in close relation to saiddie members, and a plate associated with the blower for supporting asheet after it has been acted upon by the die members, said plate beingarranged to present a substantially unobstructed path to the sheet inits travel from the die members past the blower.

6. A machine of the class described comprising die members and acleaning instrumentality comprising a blower disposed at one side inclose relation to said die members, and a perforate support for a sheetejected from said die members, said support being substantially flushwith means associated with the die members for supporting the sheetwhile being acted upon thereby.

'7. A machine of the class described comprising die members adapted tooperate on sheet material passed in working relation thereto, a blowerfor acting on said sheet material after it leaves the die members, and aperforate supporting plate for the sheet material disposed in proximityto said blower whereby the supporting plate supports the material whilebeing acted on by said blower.

GEORGE T. BALFE.

